Python: restructure: Python samples into progressive 01-05 layout (#3862)

* restructure: Python samples into progressive 01-05 layout

- 01-get-started/: 6 numbered steps (hello agent → hosting)
- 02-agents/: all agent concept samples (tools, middleware, providers, etc.)
- 03-workflows/: ALL existing workflow samples preserved as-is
- 04-hosting/: azure-functions, durabletask, a2a
- 05-end-to-end/: demos, evaluation, hosted agents
- Old files moved to _to_delete/ for review
- Added AGENTS.md with structure documentation
- autogen-migration/ and semantic-kernel-migration/ preserved at root

* fix: switch to AzureOpenAI Foundry, fix CI failures

- Switch all 01-get-started samples to AzureOpenAIResponsesClient with
  Azure AI Foundry project endpoint (AZURE_AI_PROJECT_ENDPOINT +
  AZURE_OPENAI_RESPONSES_DEPLOYMENT_NAME + AzureCliCredential)
- Add _to_delete/ and 05-end-to-end/ to pyrightconfig.samples.json excludes
- Fix test paths in packages/ that referenced old getting_started/ dirs:
  durabletask conftest + streaming test, azurefunctions conftest,
  devui conftest + capture_messages + openai_sdk_integration
- Fix workflow_as_agent_human_in_the_loop.py import (sibling import)
- Update hosting READMEs and tool comment paths
- Replace root README.md with new structure overview
- Update AGENTS.md to document Azure OpenAI Foundry as default provider

* cleanup: remove _to_delete folder, copy resource files to active dirs

All files in _to_delete/ were either:
- Exact duplicates of files in the new structure (240 files)
- Same file with only comment path updates (100 files)
- One import-fix diff (workflow_as_agent_human_in_the_loop.py)
- One superseded minimal_sample.py

Resource files (sample.pdf, countries.json, employees.pdf, weather.json)
copied to 02-agents/sample_assets/ and 02-agents/resources/ since active
samples reference them.

* fix: address PR review comments, centralize resources, remove root duplicates

- Fix type annotation in 04_memory.py (string union -> proper types)
- Fix old sample paths in observability files
- Fix grammar/spelling in observability samples
- Move sample_assets/ and resources/ to shared/ folder
- Remove 8 duplicate observability files from 02-agents root
- Update resource path references in multimodal_input and provider samples

* fix: update broken links from old getting_started paths to new structure

- Update relative paths in READMEs: getting_started/ → 01-get-started/,
  02-agents/, 03-workflows/, 04-hosting/, 05-end-to-end/
- Fix absolute GitHub URLs in package READMEs
- Fix broken link in ollama package README

* fix: convert absolute GitHub URLs to relative paths for link checker

Absolute URLs to python/samples/ on main branch 404 until PR merges.
Converted to relative paths that linkspector can verify locally.

* fix: update link for handoff sample moved to orchestrations/

* fix: update chatkit-integration README path from demos/ to 05-end-to-end/

* fix: update broken links in orchestrations README to match flat directory structure

python/samples/04-hosting/durabletask/01_single_agent/client.py

@@ -0,0 +1,121 @@
+# Copyright (c) Microsoft. All rights reserved.
+
+"""Client application for interacting with a Durable Task hosted agent.
+
+This client connects to the Durable Task Scheduler and sends requests to
+registered agents, demonstrating how to interact with agents from external processes.
+
+Prerequisites:
+- The worker must be running with the agent registered
+- Set AZURE_OPENAI_ENDPOINT and AZURE_OPENAI_CHAT_DEPLOYMENT_NAME
+  (plus AZURE_OPENAI_API_KEY or Azure CLI authentication)
+- Durable Task Scheduler must be running
+"""
+
+import asyncio
+import logging
+import os
+
+from agent_framework.azure import DurableAIAgentClient
+from azure.identity import DefaultAzureCredential
+from durabletask.azuremanaged.client import DurableTaskSchedulerClient
+
+# Configure logging
+logging.basicConfig(level=logging.INFO)
+logger = logging.getLogger(__name__)
+
+
+def get_client(
+    taskhub: str | None = None,
+    endpoint: str | None = None,
+    log_handler: logging.Handler | None = None
+) -> DurableAIAgentClient:
+    """Create a configured DurableAIAgentClient.
+
+    Args:
+        taskhub: Task hub name (defaults to TASKHUB env var or "default")
+        endpoint: Scheduler endpoint (defaults to ENDPOINT env var or "http://localhost:8080")
+        log_handler: Optional logging handler for client logging
+
+    Returns:
+        Configured DurableAIAgentClient instance
+    """
+    taskhub_name = taskhub or os.getenv("TASKHUB", "default")
+    endpoint_url = endpoint or os.getenv("ENDPOINT", "http://localhost:8080")
+
+    logger.debug(f"Using taskhub: {taskhub_name}")
+    logger.debug(f"Using endpoint: {endpoint_url}")
+
+    credential = None if endpoint_url == "http://localhost:8080" else DefaultAzureCredential()
+
+    dts_client = DurableTaskSchedulerClient(
+        host_address=endpoint_url,
+        secure_channel=endpoint_url != "http://localhost:8080",
+        taskhub=taskhub_name,
+        token_credential=credential,
+        log_handler=log_handler
+    )
+
+    return DurableAIAgentClient(dts_client)
+
+
+def run_client(agent_client: DurableAIAgentClient) -> None:
+    """Run client interactions with the Joker agent.
+
+    Args:
+        agent_client: The DurableAIAgentClient instance
+    """
+    # Get a reference to the Joker agent
+    logger.debug("Getting reference to Joker agent...")
+    joker = agent_client.get_agent("Joker")
+
+    # Create a new thread for the conversation
+    thread = joker.get_new_thread()
+    logger.debug(f"Thread ID: {thread.session_id}")
+    logger.info("Start chatting with the Joker agent! (Type 'exit' to quit)")
+
+    # Interactive conversation loop
+    while True:
+        # Get user input
+        try:
+            user_message = input("You: ").strip()
+        except (EOFError, KeyboardInterrupt):
+            logger.info("\nExiting...")
+            break
+
+        # Check for exit command
+        if user_message.lower() == "exit":
+            logger.info("Goodbye!")
+            break
+
+        # Skip empty messages
+        if not user_message:
+            continue
+
+        # Send message to agent and get response
+        try:
+            response = joker.run(user_message, thread=thread)
+            logger.info(f"Joker: {response.text} \n")
+        except Exception as e:
+            logger.error(f"Error getting response: {e}")
+
+    logger.info("Conversation completed.")
+
+
+async def main() -> None:
+    """Main entry point for the client application."""
+    logger.debug("Starting Durable Task Agent Client...")
+
+    # Create client using helper function
+    agent_client = get_client()
+
+    try:
+        run_client(agent_client)
+    except Exception as e:
+        logger.exception(f"Error during agent interaction: {e}")
+    finally:
+        logger.debug("Client shutting down")
+
+
+if __name__ == "__main__":
+    asyncio.run(main())